title: High-grade stenosis of the internal carotid artery assessed by color and power Doppler imaging.
abstract: OBJECTIVE
  Visualization of carotid artery stenosis is important to improve our understanding of the etiology of ischemic stroke. Two sonographic methods are available for visualizing carotid stenosis: power Doppler imaging (PDI) and color Doppler imaging (CDI). The purpose of this study was to compare the advantages and limitations of these methods in the evaluation of internal carotid artery (ICA) stenosis.
  
  
  METHODS
  Thirty-two patients with at least 70% extracranial ICA stenosis were included in this prospective study. All subjects were examined with CDI and PDI. Four criteria were used to evaluate diagnostic accuracy and overall efficacy: identifying the target vessel, determining the causal pathology, evaluating blood flow, and the examiner's confidence in the diagnosis.
  
  
  RESULTS
  All patients had high-grade stenosis (17 patients had 70% stenosis, 11 had 80%, 2 had 90% and 2 had pseudo-occlusions of the ICA). PDI was significantly (p < 0.05) superior to CDI in identifying the target vessel and highly significantly (p < 0.01) superior to CDI in evaluating blood flow. There were no significant differences between CDI and PDI in determining the causal pathology or in the examiner's confidence in the diagnosis.
  
  
  CONCLUSIONS
  This study demonstrates that PDI is a good additional method to CDI and should be used with it to evaluate ICA stenosis.
authors.affiliation: Department of Neurology, Technical University of Aachen, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Schmidt
authors.forename: U
authors.initials: U
authors.lastname: Sliwka
authors.forename: S G
authors.initials: SG
authors.lastname: Simon
authors.forename: J
authors.initials: J
authors.lastname: Noth
mesh_terms: D000328:Adult; D000368:Aged; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging; D016893:Carotid Stenosis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D018608:Ultrasonography, Doppler; D018615:Ultrasonography, Doppler, Color; D018084:Ultrasonography, Interventional / Q000379:methods*